US5262698A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compensation for field emission display irregularities
Assignee: Raytheon Co
•
Filing: 1991-10-31
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Granted: 1993-11-16
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Expires: 2011-10-31
Abstract
Abstract An apparatus is disclosed for controlling the brightness of a matrix-addressed flat panel CRT display of a type having intersecting column and row conductors forming, respectively, the gate and cathode electrodes of a field electron emission array. The brightness control is effected by controlling the voltages applied to the drive lines of the intersecting conductors. A waveform having progressively increasing voltage steps is sequentially applied to the row conductors. The voltages at each of the steps are preferably selected to enable electron beam currents which provide brightness levels which are twice the brightness of the previous step. Binary-coded brightness control signals are simultaneously applied to all of the column conductors. The voltages of the stepped waveform and the binary-coded signals comprise a combination of video information data and correction data which compensate for irregularities in the current emitting structure at the selected conductors. The combined voltages at the intersections of the selected conductors cause a sequence of electron emissions onto luminescing means which result in a corresponding sequence of illumination intervals.
Inventors
- 👤 Peter C. Dunham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:39
CPC Classifications
G; G09; G09G; G09G3/00; G09G3/20; G09G3/2007; G09G3/2077; G09G3/2081; G09G3/2018; G09G3/2022; G09G3/2025; G09G3/22; H; H01; H01J; H01J31/00; H01J31/08; H01J31/10; H01J31/12; H01J31/123; H01J31/125; H01J31/127; H04; H04N; H04N5/00; H04N5/44; H04N5/57; G09G3/2011
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
344 words
In a flat panel display comprising a backing structure having a surface including a first plurality of substantially parallel conductors disposed across said surface and a second plurality of substantially parallel conductors disposed across said surface, said conductors of said first plurality intersecting said conductors of said second plurality, but electrically isolated therefrom; and further comprising means at each intersection of said first and second pluralities of conductors for emitting an electron beam current therefrom in response to a potential difference between said intersecting conductors; an apparatus for controlling the electron beam current from said emitting means at each of said intersection, said apparatus comprising: first source means coupled to said first plurality of conductors for generating a first signal individually thereto, said first signal comprising a plurality of steps of different voltage levels; second source means coupled to said second plurality of conductors for generating a brightness control signal thereto, said brightness control signal being driven between a first reference potential and a second reference potential in response to a binary-coded, video input signal, wherein the voltage difference between the voltage level steps of said first signal coupled individually to said first plurality of conductors and said second reference potential of said brightness control signal coupled to said second plurality of conductors generates an electron beam current from the emitting means at the intersection of the conductor of said first plurality coupled to said first source means and the conductor of said second plurality coupled to said second source means, said electron beam current varying in accordance with said voltage difference; means coupled to said first source means for adjusting the magnitude of said first signal coupled to said first plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said first plurality of conductors; and means coupled to said second source means for adjusting the magnitude of said brightness control signal coupled to said second plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said second plurality of conductors.
Claim 2
Dependent Claim
344 words
In a flat panel display comprising a backing structure having a surface including a first plurality of substantially parallel conductors disposed across said surface and a second plurality of substantially parallel conductors disposed across said surface, said conductors of said first plurality intersecting said conductors of said second plurality, but electrically isolated therefrom; and further comprising means at each intersection of said first and second pluralities of conductors for emitting an electron beam current therefrom in response to a potential difference between said intersecting conductors; an apparatus for controlling the electron beam current from said emitting means at each of said intersection, said apparatus comprising: first source means coupled to said first plurality of conductors for generating a first signal individually thereto, said first signal comprising a plurality of steps of different voltage levels; second source means coupled to said second plurality of conductors for generating a brightness control signal thereto, said brightness control signal being driven between a first reference potential and a second reference potential in response to a binary-coded, video input signal, wherein the voltage difference between the voltage level steps of said first signal coupled individually to said first plurality of conductors and said second reference potential of said brightness control signal coupled to said second plurality of conductors generates an electron beam current from the emitting means at the intersection of the conductor of said first plurality coupled to said first source means and the conductor of said second plurality coupled to said second source means, said electron beam current varying in accordance with said voltage difference; means coupled to said first source means for adjusting the magnitude of said first signal coupled to said first plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said first plurality of conductors; and means coupled to said second source means for adjusting the magnitude of said brightness control signal coupled to said second plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said second plurality of conductors.
Claim 3
Dependent Claim
33 words
The apparatus according to claim 1 wherein said first plurality of conductors comprise row conductors and said second plurality of conductors comprise column conductors, said row conductors being orthogonal to said column conductors.
Claim 4
Dependent Claim
45 words
The apparatus according to claim 1 wherein said first signal adjusting means is coupled to said first source means, said first signal adjusting means providing adjustment of the voltage levels of each of said plurality of steps for each of said first plurality of conductors.
Claim 5
Dependent Claim
42 words
The apparatus according to claim 1 wherein said brightness control signal adjusting means is coupled to said second source means, said brightness control signal adjusting means providing adjustment of said binary-coded, video input signal for each of said second plurality of conductors.
Claim 6
Dependent Claim
56 words
The apparatus according to claim 1 wherein said first signal adjusting means provides adjustment of the voltage levels of each of said plurality of steps for each of said first plurality of conductors, and said brightness control signal adjusting means provides adjustment of said binary-coded, video input signal for each of said second plurality of conductors.
Claim 7
Dependent Claim
34 words
The apparatus according to claim 1 wherein said brightness control signal adjusting means provides adjustment of said binary-coded, video input signal of reach of the intersections of said first and second pluralities of conductors.
Claim 8
Dependent Claim
38 words
The apparatus according to claim 1 wherein the voltages at each of said plurality of steps of said first signal are selected to provide successive levels of electron beam current which are related according to a binary progression.
Claim 9
Dependent Claim
48 words
The apparatus according to claim 1 wherein said first signal adjusting means includes: means for storing digital representations of each of said plurality of voltage level steps including said predetermined correcting quantities; and means responsive to said storing means for converting said digital representations into analog voltage levels.
Claim 10
Dependent Claim
16 words
The apparatus according to claim 8 wherein said storing means includes a programmable read-only memory (PROM).
Claim 11
Dependent Claim
369 words
A flat panel display comprising: a backing structure having a first surface including a first plurality of substantially parallel conductors disposed across said surface and a second plurality of substantially parallel conductors disposed across said surface, said conductors of said first plurality intersecting said conductors of said second plurality, but electrically isolated therefrom; means at each intersection of said first and second pluralities of conductors for emitting an electron beam current therefrom in response to a potential difference between said intersecting conductors; a face structure having a second surface adjacent said first surface including means on said second surface responsive to electron beam current for providing luminescence; means for controlling the electron beam current from said emitting means at each of said intersections, said controlling means including: first source means coupled to said first plurality of conductors for generating a first signal individually thereto, said first signal comprising a plurality of steps of different voltage levels; second source means coupled to said second plurality of conductors for generating a brightness control signal thereto, said brightness control signal being driven between a first reference potential and a second reference potential in response to a binary-coded, video input signal, wherein the voltage difference between the voltage level steps of said first signal coupled individually to said first plurality of conductors and said second reference potential of said brightness control signal coupled to said second plurality of conductors is sufficient to generate an electron beam current from the emitting means at the intersection of the conductor of said first plurality coupled to said first source means and the conductor of said second plurality coupled to said second source means, said electron beam current varying in accordance with said voltage difference; means coupled to said first source means for adjusting the magnitude of said first signal coupled to said first plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said first plurality of conductors; and means coupled to said second source means for adjusting the magnitude of said brightness control signal coupled to said second plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said second plurality of conductors.
Claim 12
Dependent Claim
369 words
A flat panel display comprising: a backing structure having a first surface including a first plurality of substantially parallel conductors disposed across said surface and a second plurality of substantially parallel conductors disposed across said surface, said conductors of said first plurality intersecting said conductors of said second plurality, but electrically isolated therefrom; means at each intersection of said first and second pluralities of conductors for emitting an electron beam current therefrom in response to a potential difference between said intersecting conductors; a face structure having a second surface adjacent said first surface including means on said second surface responsive to electron beam current for providing luminescence; means for controlling the electron beam current from said emitting means at each of said intersections, said controlling means including: first source means coupled to said first plurality of conductors for generating a first signal individually thereto, said first signal comprising a plurality of steps of different voltage levels; second source means coupled to said second plurality of conductors for generating a brightness control signal thereto, said brightness control signal being driven between a first reference potential and a second reference potential in response to a binary-coded, video input signal, wherein the voltage difference between the voltage level steps of said first signal coupled individually to said first plurality of conductors and said second reference potential of said brightness control signal coupled to said second plurality of conductors is sufficient to generate an electron beam current from the emitting means at the intersection of the conductor of said first plurality coupled to said first source means and the conductor of said second plurality coupled to said second source means, said electron beam current varying in accordance with said voltage difference; means coupled to said first source means for adjusting the magnitude of said first signal coupled to said first plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said first plurality of conductors; and means coupled to said second source means for adjusting the magnitude of said brightness control signal coupled to said second plurality of conductors, wherein the magnitude adjustment comprises a predetermined correcting quantity specific to each of said second plurality of conductors.
Claim 13
Dependent Claim
43 words
The flat panel display according to claim 10 wherein said first plurality of conductors comprise row conductors and said second plurality of steps for each of said first plurality of conductors comprise column conductors, said row conductors being orthogonal to said column conductors.
Claim 14
Dependent Claim
27 words
The flat panel display according to claim 10 wherein said first signal adjusting means provides adjustment of the voltage levels of each of said plurality of conductors.
Claim 15
Dependent Claim
31 words
The flat panel display according to claim 10 wherein said brightness control signal adjusting means provides adjustment of said binary-coded, video input signal for each of said second plurality of conductors.
Claim 16
Dependent Claim
58 words
The flat panel display according to claim 10 wherein said first signal adjusting means provides adjustment of the voltage levels of each of said plurality of steps for each of said first plurality of conductors, sand said brightness control signal adjusting means provides adjustment of said binary-coded, video input signal for each of said second plurality of conductors.
Claim 17
Dependent Claim
36 words
The flat panel display according got claim 10 wherein said brightness control signal adjusting means provides adjustment of said binary-coded, video input signal for each of the intersections of said first and second pluralities of conductors.
Claim 18
Dependent Claim
40 words
The flat panel display according to claim 10 wherein the voltages at each of said plurality of steps of said first signal are selected to provide successive levels of electron beam current which are related according to a binary progression.
Claim 19
Dependent Claim
50 words
The flat panel display according to claim 10 wherein said first signal adjusting means includes: means for storing digital representations of each of said plurality of voltage level steps including said predetermined correcting quantities; and means responsive to said storing means for converting said digital representations into analog voltage levels.
Claim 20
Dependent Claim
18 words
The flat panel display according to claim 17 wherein said storing means includes a programmable read-only memory (PROM).
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-11-15 | 1997-05-17 | 1997-11-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-11-15 | 2001-05-17 | 2001-11-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-11-15 | 2005-05-17 | 2005-11-16 | $7700.00 | Window Closed / Lapsed |